Press molding machine



c. w. MCCREERY 7 2,393,549

. PRESS MOLDING MACHINE Jan. 22', 1946.

Filed April 22, 1945 2 Sheets-Sheet 1 Ceci? W/WC/zmy Jan. 22, 1946. c. w. MCCREERY 'PRESS MOLDING MACHINE Filed April-22, 1943 2 sheets sheet 2 Patented 22, 1946 PRESS MOLDING MAC:

Owens-Illinois Glass 7 Application AprllZZ, 1M3, Serial No. M3992 (Gil. d'iitl 7 Claims.

invention relates to press molding machines i'or molding glass articles and includes means for to a i apertures in the articles during the molding operation.

An object of the invention is to provide a novel apparatus for accurately cutting or forming apertures in molded articles. More particularly, the invention provides in combination with a press mold and plunger for molding hollow glass articles, auxiliary means for cutting an aperture in the molded article, concurrently with the moveent oi the plunger by which the article is olded.

a further object oi the invention is to provide means ior accurately centering the press plunger with a stationary die which cooperates therewith d thereby accurately cutting or forming an aperture in the molded article.

Other objects oi the invention will appear hereinafter. 1

helerring to the accompanying drawings: 7

Fig. l is a part-sectional elevation of a press molding machine emg the principles of my invention. I

Fig. 2 is a part-sectional elevation showing the mold and plunger with the latter in its lifted tion.

Fig. 3 is a similar view but showing the plunger lowered.

Fig. i is a iragmentary view showing the plunger liited to an intermediate position following the molding operation. 1

Reierring particularly to Fig. 1, the invention is shown as applied to and forming a part oi a p molding machine which, except as to the particular mechanism for forming the apertures in the molded articles, is in the main, of conventional construction. The machine comprises a press plunger head ill and plunger rod II, lifted d lowered by a. piston motor comprising a piston 02 which reciprocates within a cylinder It mounted on the machine frame It.

A sectional mold i5 comprises mold halves or sections mounted on a mold bottom plate l6 and pivoted to swing about a pivot pin II. The mold sections are locked together for the molding op- Jill slidable up and down therein, the downward movement being limited by stop nuts it threaded on said rods. Coil compression springs it on said rods are held under compression between the head ill and the plate lh The parts as thus far described are of conventional construction. The mechanism for forming apertures in the molded articles in accordance with the present invention will now be described. An anvil it has a stationary mounting in the base plate it and is secured in position therein by a cap screw ti. The plunger Elli is lormed with a central ong extending vertically there-' through in which is mounted an annular shearmember or ring lid secured by bolts lit. The

vil it is formed with acircular shearing edge conical surface ill, for cooperation with the conioration by a locking. device 18. A press plunger 20 is connected to the head for vertical reciprocating movement into and out of the mold cavity 2|. A plunger stem or extension 22 is attached to the plunger by bolts 23. A pressure ring 24 which surrounds the plunger is attached by bolts 2! to a plate 2! suspended from the head II by means ot a pair of vertical rods 21 which extend through the head Ill and are M which cooperates with the shearing ring it as hereinalter described for shearing the glass to form. an opening through the molded article.

Cooperating with the anvil it is an auxiliary or secondaryplunger is mounted for limited vertical reciprocating movement within the main plunger fill. Thepluhger ill! is fitted to slide within the shearing ring it and serves, in cooperation with the anvil it, as a means for accurately aligning the shear-mg ring with the anvil for the shearing operation, all as fully set forth hereinafter.

A plunger cap it (Fig. 2) seats on the plunger lit and is held thereon by a lock nut 31 threaded on a stud bolt 3% which is threaded into the plunger it. inner coil compression spring 39, mounted on the bolt til, is held under compression between the loch nut ill and a washer Ml on said bolt. outer coil compression spring M, surroun the spring til, is held under compression between the washer to and the cap it.

The plunger 35 is formed at its lower end with a irusto-conical recess M having conical or taperedwalls it. The anvil is formed with a irusto-conical extension 46 having a tapered or cally recessed plunger 35. The inclined surfaces 45 and Ill are preferably exactly parallel so that when the plunger is lowered, the extension 41 of the anvil fits accurately within the recess M and thus serves to accurately center and align the plunger 20, and particularly the shearing ring 32, with the anvil for the shearing operation.

The operation is as follows:

When the press head In is in its lifted position, a charge or gob 48 of molten glass is placed within the mold cavity 2|. The head It is then lowered so that the pressure ring 24 is seated on the mold and the plunger 20 enters the mold cavity. The auxiliary plunger 35, as shown in Fig. 2. is in its lowermost position relative to the main plunger lunger. The frusto-conical surfaces during this I movement align themselves concentrically upon the same common vertical center line. That is a to say, the anvil 30 being held in fixed position, aligns the plunger 35, and with it the main plunger 20 and shearing ring 32 for the cutting operation.

As the plunger moves downward and approaches the anvil 30, the glass directly over the I anvil and between it and the auxiliary plunger 35, is forced to spread out laterally, forming a comparatively thin layer between the anvil and the plunger. The resistance offered to this spreading of the-glass results in an increased pressure on the'upper surface area of the anvil and the bottom surface of the plunger 35 directly thereover, such area being co-extensive laterally with the area of the aperture which is formed in the molded article during the final downward movement of the main plunger. This added pressure increases as the frusto-conical surfaces approach each other. The compression force of the coil springs may be sufficient to prevent retraction of the plunger 35 within the press plunger before it seats on the frusto-conical extension 46 of the anvil with the inclined wall surfaces t5 and 41 in contact with each other.

When the auxiliary plunger 35 is thus seated on the anvil and accurately centered thereon, the continued downward movement of the plunger head 20 causes the shearing ring 32 to move downwardly into shearing contact with the shearing edge 34 of the anvil 30, thereby severing the thin layer or fringe of glass remaining between the anvil and the plunger 35. The anvil and plunger are designed to provide a narrow, marginal space between their opposing flat, annular surfaces which surround the base of the projection 46. During the final downward movement of the plunger 20 after the shearing operation, the glass is forced upwardly within the mold cavity around the main plunger to the pressure ring 24, thereby completing the formation of the molded article.

Modifications may be resorted to within the spirit and scope of my invention.

plunger mounted for reciprocation within said opening, said projecting element being positioned and arranged to provide a stop for the auxiliary plunger for arresting the auxiliary plunger when stationary anvil projecting upwardly within the mold cavity, a main press plunger movable vertically into and out of the mold cavity, and

plunger having a central opening in register with the anvil, an auxiliary plunger mounted within said opening and movable up and down therein, and a compression spring holding the said auxiliary, plunger in its lowered position relative to the main plunger, the auxiliary plunger and anvil having oppositely positioned cooperating tapered surfaces so positioned and arranged that they are brought together and cause the anvil to center the plungers and form'a stop for the auxiliary plunger for arresting it during the downward movement of the main plunger, said anvil having a shearing edge to cooperate with the main plunger for shearing the glass surrounding the anvil.

3. A press molding machine comprising a stationary mold having a mold cavity therein, a stationary anvil projecting upwardly within the mold cavity, a main press plunger movable vertically into and out of the mold cavity, said plunger, having a central opening in register with the anvil, an auxiliary plunger mounted within said opening and movable up and down therein, and a compression spring holding the said auxiliary plunger in its lowered position relative to the main plunger, said anvil being arranged and positioned to form a stop for the auxiliary plunger for arresting it during the downward movement of the main plunger, said anvil having a shearing edge to cooperate with the main plunger for shearing the glass surrounding the anvil, the anvil and auxiliary plunger having opposite'ly disposed frusto-conical surfaces which fit together when the auxiliary plunger is artested during the downward movement of the main plunger and thereby provide centering means by which the auxiliary plunger is centered and aligned with the anvil, said auxiliary plunger forming a guide for the main plunger during the final downward movement of the latter.

4. A press molding machine comprising a mold having a mold cavity, an anvil mounted in position to project within the mold cavity, a main plunger movable into and out of the mold cavity and having an opening in register with said anvil, and an auxiliary plunger mounted within said opening and movable toward and from the anvil therein, said anvil being arranged to provide a stop for the auxiliary plunger, the auxiliary plunger and the anvil having cooperating tapered surfaces which are-brought together and fit one within the other and thereby center the auxiliary plunger when the latter is moved into contact with the anvil.

5. The combination of a sectional mold, a bottom plate on which the mold sections are mounted to swing to and from a closed position, said mold having an upwardly facing mold cavity, an anvil mounted in said bottom plate and projecting upwardly within the mold cavity, a

the main plunger reaches an intermediate posi- 1 tion during its downward movement, the said projecting element and auxiliary plunger having oppositely disposed contacting tapered guiding surfaces by which the said plung 's are centered relatively to the mold.

2. A press molding machine comprising a stationary mold having a mold cavity therein, a

main plunger positioned over the mold cavity and movable up and down therein, said plunger having an opening therein, an auxiliary plunger mounted for up and down movement within said opening, and a compression spring holding the auxiliary plunger in its lowered position relative to themain plunger, said anvil being positioned in the path of the auxiliary plunger and forming a stop therefor by which the auxiliary plunger is arrested as the main plunger, during its downward movement, reaches a point near the limit of its downward movement, said anvil and auxiliary plunger having cooperating, tapered surfaces by which the auxiliary plunger is accurately centered. and held during the final movement of the main plunger.

6. The combination of a sectional mold, a bottom plate on which the mold sections are mounted to swing to and from a closed position, said mold having an upwardly facing mold cavity, an anvil mounted in said bottom plate and projecting upwardly within the mold cavity, a main plunger positioned over the mold cavity and movable up and down therein, said plunger having an opening therein, an auxiliary plunger mounted for up and down movement within said opening, a compression spring holding the auxiliary plunger in its lowered position relative to the main plunger, said anvil being positioned in the path of the auxiliary plunger and forming a stop therefor by which the auxiliary plunger is arrested as the main plunger, during its downward movement, reaches a point near the limit of its downward movement, said anvil and auxiliary plunger having cooperating, tapered surfaces by which the auxiliary plunger is accurately centered and held during the final movement of the main plunger, and a, shearing ring mounted in said opening in the main plunger and surrounding said auxiliary plunger, said ring having a shearing edge cooperating with the edge of said anvil for severing the glass overlying the anvil and thereby forming an opening through the molded article.

7. The combination of a sectional mold, a bottom plate on which the mold sections are mounted to swing to and from a closed position, said mold having an upwardly facing mold cavity, an anvil mounted in said bottom plate and projecting upwardly within the mold cavity, a main plunger positioned over the mold cavity and movable up and down therein, said plunger having an opening therein, an auxiliary plunger mounted for up and down movement within said open- 7 ing, said anvil being positioned in the path of the auxiliary plunger and forming a stop therefor by which the auxiliary plunger is arrested as the main plunger, during its downward movement, reaches a point near the limit of its downward movement, said anvil and auxiliary plunger having cooperating, tapered surfaces by which i the auxiliary plunger is accurately centered and held during the final movement of the main plunger;

CECIL WAYNE MCCREERY. 

